Most of us think there are only 2 systems that can be affected by that Traction Control switch but actually there are 4 (main systems):
Antilock Braking Sytem (ABS)
Traction Control System (TCS)
Vehicle Electronic Stabiltiy (VES)
Engine Drag Control (EDC)
Each of these systems has a very specific purpose even though they may share control modules and sensors. I'll get into them in a sec...
The module which controls these systems is the Electronic Brake Control Module (EBCM). This module does far more than just handle braking - it is the module which controls everything associated with tires being on the pavement and the car being in a straight line.
Some of the sensors which return data back to the EBCM include: the wheel speed sensor, the lateral accelerometer sensor, the yaw rate sensor and the steering wheel positioning sensor. Based on the names alone, you can imagine the type of calculations the EBCM has been engineered to make.
Anyways, getting back to the traction/braking systems - here's a bit of a run down in terms of what each system actually does.
ABS
Nothing you don't already know except that the system can release, hold or increase the amount of brake pressure to any wheel independently of each others requirement. It cannot however, increase more brake pressure than what the master cylinder is dishing out so if you are in a jam and your ABS is on, jump on that brake pedal as hard as you can so you can give the system the max amount of braking pressure if it needs it. If it's too much, don't worry, the system will figure out which wheel(s) to lighten up on.
TCS
The TCS actually has a "graduated" design. When the EBCM detects drive wheel slippage, the FIRST thing it does is sends a signal to the ECM telling it to reduce the amount of torque it is sending to those wheels. How does the ECM do that? It retards the timing and starts shutting down fuel injectors. (anyone starting to see how having TCS on affects seat of your pants acceleration?).
If this is not enough to control wheel spin, then the EBCM will begin applying brake pressure to the drive wheels in conjunction to what the ECM is doing. All this happens in miliseconds.
EDC
When a driver let's of the gas rapidly or downshifts to cause the rear tires to skid, this system will actually have the EBCM send a message to the ECM telling it to increase torque to the rear wheels (throttle increase) so that wheel lockup is prevented.
VES
The Camaro really does calculate the yaw rate in order to take the car out of a slide. In simple terms, the yaw rate is the amount of angle the car is sliding sideways. So if you want to drift the car, you must turn this system off or it will constantly be trying to bring the car back.
How does the system determine yaw rate? It uses 3 parameters: position of the steering wheel, the speed of the vehicle and sideways acceleration of the vehicle.
This system will generally kick in under performance driving but it will also kick in when you are driving on a loose gravel road and the rear end kicks out on you. This system will kick in even if you slide out on a gravel road while your foot is off the gas or brake pedal.
So all this to say what? There is a lot more going on in this car than you might think. The car gives you the ability to turn these systems off in various ways but it's there if you need it!
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